Ultrawideband (UWB) signals came into use as a result of researchers' efforts to learn as much as possible about radar targets. The current state of UWB radar science follows interest in UWB signal applications. High resolution radars have been designed for the recognition of airborn and space targets, and UWB signals have been adapted to conventional radars and theoretical models. This volume explores principal issues in both the theoretical description of ultra-wideband radar signals and their computer processing. Emphasis is placed on the possibility of modelling and measuring UWB signal waveforms as a leading source of information about a target. There is detailed discussion of mathematical models for radar targets, and the statistical processing of scattered signals. The efficiency of the regularizing algorithms suggested is illustrated with a description of experimental data processing.